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排序方式: 共有196条查询结果,搜索用时 15 毫秒
121.
Impact of physicochemical characteristics on the oxidative stability of fish oil microencapsulated by spray-drying 总被引:1,自引:0,他引:1
Drusch S Serfert Y Scampicchio M Schmidt-Hansberg B Schwarz K 《Journal of agricultural and food chemistry》2007,55(26):11044-11051
The aim of the present research was to identify principal parameters determining the oxidative stability of microencapsulated fish oil. Microcapsules were prepared by spray-drying using different types of n-octenylsuccinate-derivatized starch, gum Arabic, sugar beet pectin, sodium caseinate, and/or glucose syrup. Two principal components to classify the different microcapsules accounting for up to 79% of the variance were identified. The principal components were determined by physicochemical parameters reflecting the emulsifying ability of the encapsulant and the drying behavior of the parent emulsion. Microcapsules, which were identified by principal component analysis to be significantly different, exhibited a low stability upon storage, showing that the principal components and, thus, the underlying physicochemical parameters analyzed in the present study are correlated with core material stability. 相似文献
122.
Proverbio D Spada E Perego R Grieco V Lodi M Di Giancamillo M Ferro E 《Journal of the American Animal Hospital Association》2012,48(2):132-138
This report describes multiple endocrine neoplasia in a dog, which is a rare hereditary disorder characterized by the presence of two or more neoplasms of different endocrine tissues within a patient. A 14 yr old dog was evaluated for polyuria/polydipsia, polyphagia, and abdominal enlargement. Adrenal-dependent hyperadrenocorticism with concomitant left thyroid enlargement and a presumed abdominal metastatic lesion were diagnosed by an adrenocorticotropic hormone stimulation test, ultrasonography, and computed tomography. Trilostane therapy was initiated and resolved the clinical signs for 2 yr at which time the dog presented with left testicular enlargement. The dog was euthanized and was diagnosed with adrenocortical carcinoma, thyroid carcinoma, an abdominal mass compatible with a metastatic lymph node, and bilateral interstitial cell testicular adenomas. To the authors' knowledge, this is the first report to describe the concomitant association of these types of endocrine neoplasms in a dog. The concomitant presence of these neoplasms could represent a potential variant of multiple endocrine neoplasia; however, the presence of the interstitial cell testicular adenomas may have only been an incidental finding. If any of these tumors are diagnosed, veterinarians should perform a thorough clinical assessment to evaluate for the presence of additional endocrine neoplasms or hyperplasia. 相似文献
123.
Matteo Campioli Caroline Vincke Mathieu Jonard Vincent Kint Gaston Demarée Quentin Ponette 《Journal of Forest Research》2012,17(1):1-18
Reviews of the current statuses of forests and the impacts of climate change on forests exist at the (sub)continental scale,
but rarely at country and regional levels, meaning that information on causal factors, their impacts, and specific regional
properties is often inconsistent and lacking in depth. Here, we present the current status of forest production and biogeochemistry
and the expected impacts of climate change on them for Belgium. This work represents a case study for the temperate oceanic
zone, the most important bioclimatic zone in northwestern Europe. Results show that Belgian forests are mainly young, very
productive, and have a high C-sequestration capacity. Major negative anomalies in tree vitality were observed in the 1990s
and—as result of disturbances—in the last decade for sensitive species as poplars and European beech. The most severe disturbances
were caused by extreme climatic events, directly (e.g. storms) or indirectly (e.g. insect outbreaks after a mild autumn with
an early/severe frost). Because of atmospheric deposition and soil fertilization (due to the previous use of the land), nutrient
stocks of Belgian forests are likely to sustain the future enhancement in productivity which is expected to follow the increase
in atmospheric CO2 concentration that will occur in years to come. However, in the long term, such (enhanced) forest production is likely to
be limited by nutrient deficiencies at poor sites and by drought for sensitive species such as beech and (particularly) Norway
spruce. Drought conditions will likely increase in the future, but adverse effects are expected on a relatively limited number
of tree species. The potential impacts of windstorms, insects and fungi should be carefully investigated, whereas fires are
less of a concern. 相似文献
124.
Giorgio Vacchiano Matteo Garbarino Enrico Borgogno Mondino Renzo Motta 《European Journal of Forest Research》2012,131(4):989-1000
Scots pine (Pinus sylvestris L.) forests of many inner Alpine valleys have recently displayed a quick loss of vitality. A decline disease has been suggested as the cause, with drought as the main predisposing factor and the additional contribution of biotic agents inciting tree dieback. This study is focused on Valle d’Aosta, a dry, inner-Alpine region in NW Italy. We inferred vitality changes between years 2000 and 2007 by computing reductions in enhanced vegetation index (EVI). Image differencing was carried out on pre-processed Moderate Resolution Imaging Spectroradiometer (MODIS) imagery taken in late springtime and validated against ancillary ground truth. We: (1) tested whether EVI reductions in Scots pine forests were significantly higher than those of a control species and of a wetter region for the same species, (2) analyzed decline incidence as a function of site and topographic variables, and (3) assessed the relative influence of site and stand structure on decline probability by means of path analysis. Mean EVI in the study area increased due to an early onset of the 2007 growing season. Nevertheless, the incidence of decline was 6.3% and significantly greater for Scots pine than the control species and site. Low-elevation, northerly exposed sites exhibited the highest incidence of decline. Path analysis suggested that the most important determinants of decline probability were slope, solar radiation, and stand sparseness. 相似文献
125.
Matteo Rossanese DVM SPSA CertAVP MSc MRCVS Brandan Wustefeld-Janssens BSc BVSc CertAVP DECVS MRCVS Cleo Price BVSc MRCVS Ben Mielke BVSc MRCVS Samantha Woods BSc MA VetMB CertSAS DECVS FHEA MRCVS Nicola Kulendra BVetMed CertVDI DECVS MRCVS Guillaume Chanoit DEDV MSc PhD DACVS DECVS FHEA 《Veterinary surgery : VS》2020,49(4):659-667
126.
Bonoli M Bendini A Cerretani L Lercker G Toschi TG 《Journal of agricultural and food chemistry》2004,52(23):7026-7032
Capillary electrophoresis (CE) can be effectively used as a fast screening tool to obtain qualitative and semiquantitative information about simple and complex phenolic compounds of extra virgin olive oil. Three simple phenols (tyrosol, hydroxytyrosol, and vanillic acid), a secoiridoid derivative (deacetoxy oleuropein aglycon), and two lignans (pinoresinol and acetoxypinoresinol) were detected as the main compounds in extra virgin olive oils by high-performance liquid chromatography (HPLC) and capillary zone electrophoresis (CZE). Spectrophotometric indices, radical scavenging activity, and oxidative stability of extra virgin olive oil samples obtained from olives hand-picked at different ripening degrees were statistically correlated with the CZE and HPLC quantification. The concentration of phenols in extra virgin olive oil decreased with ripeness of olive fruits. The high correlations found between CZE and the other analytical results indicate that CE can be applied as a rapid and reliable tool to routinely determine phenolic compounds in extra virgin olive oils. 相似文献
127.
Gary E Harmant James Lynch Matteo Lorito 《浙江大学学报(农业与生命科学版)》2004,30(4):440-440
Trichoderma spp. probably have a role in remediation of polluted soils and waters. Highly rhizosphere competent strains persist on roots for an extended period of time (at least months) and continuously interact with the plants. They can increase general plant and root growth and increase uptake of a variety of materials. This makes the Trichoderma-plant interaction highly attractive for use in phytoextraction technologies. Moreover, Trichoderma spp. are resistant to a wide range of toxic… 相似文献
128.
Varoon K Zhang X Elyassi B Brewer DD Gettel M Kumar S Lee JA Maheshwari S Mittal A Sung CY Cococcioni M Francis LF McCormick AV Mkhoyan KA Tsapatsis M 《Science (New York, N.Y.)》2011,334(6052):72-75
Thin zeolite films are attractive for a wide range of applications, including molecular sieve membranes, catalytic membrane reactors, permeation barriers, and low-dielectric-constant materials. Synthesis of thin zeolite films using high-aspect-ratio zeolite nanosheets is desirable because of the packing and processing advantages of the nanosheets over isotropic zeolite nanoparticles. Attempts to obtain a dispersed suspension of zeolite nanosheets via exfoliation of their lamellar precursors have been hampered because of their structure deterioration and morphological damage (fragmentation, curling, and aggregation). We demonstrated the synthesis and structure determination of highly crystalline nanosheets of zeolite frameworks MWW and MFI. The purity and morphological integrity of these nanosheets allow them to pack well on porous supports, facilitating the fabrication of molecular sieve membranes. 相似文献
129.
CLIP identifies Nova-regulated RNA networks in the brain 总被引:1,自引:0,他引:1
130.
Ferrari R Pellegrini M Horwitz GA Xie W Berk AJ Kurdistani SK 《Science (New York, N.Y.)》2008,321(5892):1086-1088